Upgrading network card driver on FreeBSD 6.2 ?

[Nomad]

Just recently found out that FreeBSD 6.2 doesn't have native support for my
network card:

  Broadcom NetXtreme II BCM5708 1000Base-T (B2)

It does work on machines with the B0 rev.   In order to upgrade the driver,
is it sufficient to replace the contents of:

     /usr/src/sys/dev/bce/

??   Or are there other src files I also need to replace?


While browsing one of the ftp mirrors I noticed there were
6.3-RELEASEimages available but I'm always wary of using a brand new
release.

Any information would be appreciated.